- Certified Irrigation Technician Controllers and Programming Flashcards

A homeowner reports that their irrigation system runs at the correct times but Zone 3 never activates. The controller display shows Zone 3 is programmed and running. The most likely cause is:

Answer: A broken or shorted zone wire or failed solenoid on Zone 3's valve

If the controller shows Zone 3 is running but no water flows on that zone while other zones work, the problem is isolated to Zone 3's circuit — either the field wire is broken/shorted or the valve solenoid has failed. A master valve or rain sensor issue would affect all zones.

What is the purpose of a master valve in an irrigation system?

Answer: To act as a safety valve that opens only when the controller activates a zone, preventing water flow when no zones are running

A master valve is installed on the mainline and is controlled by the controller's master valve circuit. It opens only when the controller activates a zone, ensuring that no water flows through the mainline when the system is idle, preventing waste from leaks or broken pipes.

A commercial property requires irrigation between midnight and 6:00 AM only. The system has 24 zones each requiring 15 minutes of run time. How many programs with separate start times are needed to fit within the watering window?

Answer: 1 program with 1 start time

With 24 zones at 15 minutes each, the total run time is 360 minutes (6 hours). Since the zones run sequentially within a program, one program with a single start time at midnight will complete all zones by 6:00 AM, exactly fitting the watering window.

What does a 'seasonal adjust' or 'water budget' feature on a controller allow the technician to do?

Answer: Apply a percentage adjustment to all programmed run times without changing individual station times

The seasonal adjust (water budget) feature applies a percentage multiplier to all run times. For example, setting it to 75% would reduce all zone run times by 25%. This allows quick seasonal adjustments without reprogramming each zone individually.

A flow sensor is connected to the irrigation controller. What information does it provide to help manage the system?

Answer: Real-time flow rate data that can detect leaks, broken pipes, or clogged nozzles by comparing actual flow to expected flow

A flow sensor measures the actual flow rate through the mainline and reports it to the controller. The controller compares this to expected flow rates for each zone and can detect high-flow conditions (broken pipe) or low-flow conditions (clogged nozzles or closed valves).

When programming an irrigation controller, what is the difference between a 'program' and a 'start time'?

Answer: A program defines which zones run and for how long; a start time defines when the program begins its sequence

A program is a complete watering schedule that includes assigned zones, their run times, and watering days. A start time tells the controller when to begin running that program's zone sequence. Multiple start times on one program cause it to run multiple times per day.